Engine starting mechanism



Oct 5- R. M. NARDONE. 2,386,812

ENGINE STARTING MECHANISM Filed Nov. 20, 1940 2 Sheets-Sheet l Rofizeo MNamlome Patented Oct. 16, 1945 ENGINE STARTING MECHANISM Romeo M. Nardone, Westwood, N. J assignor to Bendix Aviation Corporation, South Bend, Ind., a corporation of Delaware Application November 20, 19.40, SerialNo. 366.501

6 Claims. (01. 123-179) This invention relates to engine starting mechanism and more particularly to means for controlling both the energization of such a starting mechanism and the establishment of driving connection betweenthe mechanism and the engine to be started.

In engine starters of the inertia type, such as that disclosed in the Lansing Patent No. 1,833,948, electromagnetic means distinct from the starter prime mover serve to actuate the engine enga ing clutch after such prime mover has been deenergized. That is, the prime mover (shown as an electric motor in the aforesaid Lansing patent, and similarly shown in the preferred embodiment of the present invention) is first energized for a period of time sufficient to accelerate the starter flywheel (constituting the inertia element of the device) to the desired speed, whereupon switch mechanism is manually operative to de-energize the motor and at the same time energize a solenoid which actuates the engine engaging element.

The present invention involves a deviation from the controlling means and method of operation of the above identified patent in the sense that instead of de-energizing the motor concurrently with the meshing (engine engaging) operation, the motor is caused to remain energized even after meshing is effected, and the energy stored in the starter flywheel is held in reserve for use only after a period of cranking directly from the motor to the engine. Such preliminary period of direct cranking by the motor, with the flywheel disconnected, relieves the flywheel of the comparatively heavy drain upon its stored energy which it ordinarily undergoes by reason of the high resistance of the engine parts during the breakaway efiort. By delaying the coupling of the energized flywheel until such breakaway resistance has been overcome, the cranking period is lengthened to an extent corresponding to the savingin energy, since the flywheel will then deliver up its'energy at a much steadier and more gradual rate.

In this respect the present invention utilizes the major features of the method of operation disclosed and claimed in my Patent No. 2,038,191, granted April 21, 1936; but there are important departures in construction and inter-relation of parts, and also in the details of the several steps constituting a complete cycle of operation; which departures in construction, inter-relation of parts, and mode of operation constitute objects of the present invention. Further objects will appear more fully from an examination of the followin detailed description when read with reference, to the accompanying drawings showing one embodiment of the present invention.

It is to be understood, however, that the drawings are merely illustrative and are not designed to indicate the limits of the invention, reference I being had for this purpose to the appendedclaims.

In the drawings there is shown in Fig. 1 a representation,ipartly in section and partly in outline, of one type of. engine starting mechanism to which the present invention is; applicable; Fig. 2 is a diagram of the control circuits'and parts; and

Figs. 37 show different relative positions of certain of the parts of Fig. 2. Referring to the drawings, the starter mechanism is shown as embodied in a casing 4, where.- in is rotatably mounted an inertia element or flywheel 5 which may be automatically rotated by an electric, motor 6, or which may be manually rotated by alternatively operable means as in my earlier patent. The flywheel is adapted to drive.

a clutch member 8 through suitable mechanism mounted in housing 4, as in my earlier patent; and when said flywheel has been brought to a sufliciently high speed of rotation, clutch member 8 is adapted to be thrown into engagement with a corresponding clutch member! provided on the shaft ll] of the engine to be started. The connections between the flywheel 5 and the driven member 8 may be of any desired form including reduction gears l6 and I1. and torque limiting clutch mechanism as illustrated and described in greater detail in, the Lansing patent above identified.

The driving connections from the motor 6 to the flywheel 5 include a disengageable clutch whereby the flywheel may be accelerated by the delivery thereto of energy developed in the motor 6, and thereafter the flywheel allowed to run free of the motor so that the motor may function to directly crank the engine member 9, the efiectiveness of the flywheel as a driving agency being thus delayed (as in my earlier patent) until after a preliminary period of direct cranking. As shown, the drive also includes a short shaft 28. splined at one end to a cup-shaped element 29 constituting the driven member of an overrunning clutch having driving rollers 3| (as in my earlier patent) and a driving inner race 33 splined to the outer portion 34 of the armature shaft 35 of the motor. The disengageable clutch is shown in form of a pair of cooperating conical surfaced friction elements 31 and 38, the former clutch member 38 in engagement with flywheel 5 except when released by the means to be described.

Th'e clutch releasing means is adapted to act upon the circular flange 56 on the outer race of thrust bearing 53, to move the latter to the right;

element 4 I, the latter follows along.

A yoke member 55 (illustrated schematically in Fig, 2) is mounted to rock about a pivot bearing, and as it rocks about said bearing it exerts a thrust upon the flange 56 of thrust bearing 53, to move said thrust bearing and h'ence the clutch 4| to the right to disengage the clutch. The rocking of the yoke 55 follows energization of solenoid 1| (Fig. 2) whose plunger 12 terminates in a pivotal connection with the free end of said yoke 55, to actuate the latter.

A motor accelerating switch I4 is secured to the rear of plunger 12, and moves therewith, so that when the cone clutch is disengaged by the solenoid 1i, switch I4 is placed in circuit with motor 6.

With this arrangement the operator is relieved of the necessity of holding the cone clutch disengaged by manually applied force; the manual control of my former Patent No. 2,038,191 being replaced by the electromagnetic control shown in Fig. 2.

The control for thi starter further includes a push-pull switch having contacts 18 connected to the motor windings and others (19) connecting to the solenoid 1|. A direct link is diagrammatically illustrated in Figs. 2 to 5 as extending from the switch handle 80 to the engine engaging member 8, through a lost-motion connection 8|, similar in construction and effect to that which is illustrated in Fig. 4 of the drawings of my Patent No. 2,156,602, granted May 2, 1939, but in addition, permitting limited twisting movement of handle 80 in relation to jaw clutch element 8, for a purpose to presently appear.

The disk 83, which is adapted to bridge the contacts 19, has a current conducting portion 84 (Figs. 6 and '7) and non-conducting portions 85, 86 and 81. Except when twisted for the final stage of the cycle of operation (Fig. 5) the portions 85 and 86 lie in horizontal alignment (Fig. 6) and therefore are not in position to interfere with closure of a circuit through contacts 19; but when'turned (to the position indicated in Fig. 7) by the twisting of handle 80, they render said contacts 19 inoperative.

From the foregoing it will be seen that the first step is to move the handle 80 from the at rest position (Fig. 2) to the operating position No. I (Fig. 3). In this position motor 6 is energized by current flowing from source 81 by way of contacts 18. Contacts 19 being unbridged, solenoid 1| remains de-energized, therefore cone clutch 31, 38 is engaged (by spring 5|) and the flywheel is caused to rotate with the motor 6. When the flywheel is sufliciently accelerated, the operator moves handle 80 to position No. 2 (Fig.

' and as the inner race is riveted to the cone clutch 4) whereupon the clutch 8 is shifted to engage the engine member 9, and contacts 19 are bridged, causing current to flow to solenoid 1|, to disengage cone clutch 31, 38, wherefore the flywheel floats idly on its bearings. The motor 6 remains energized; the circuit thereto being shifted, however to the path which includes the switch l4 rather than the switch 18, the latter being now open.

In this position No. 2 (Fig. 4) the engine is turned over by the direct cranking action of the motor driven gear train, independently of the freely spinning previously accelerated flywheel. Now, to complete the cranking action, motor 6 is de-energized and flywheel 5 reconnected to the gear train. This is accomplished by twisting the handle to the final operating position (Fig. 5) whereupon solenoid 1| is deenergized (by the breaking of the circuit at 85, 86) and the motoralso (by the breaking of the circuit at M). The resurgence of spring 5|, of course, operates to re-engage clutch 31, 38 to permit the flywheel inertia to be transferred to the engine by way of the still engaged elements 8 and 9. As this occurs the flywheel driven elements overrun the motor, at rollers 3|.

Upon completion of the cranking process, and resultant overrun at the point 9, the operator permits the parts to return to the "at rest position (Fig. 2).

What is claimed is:

1. In an engine starter, in combination with an engine engaging membeig'means for rotating said engine engaging member, said rotating means including a motor and gear train, additional rotating means including a flywheel and a releasable clutch connecting said flywheel to said gear train, means for moving said engine engaging member to engine engaging position, and means for electrically holding said clutch in released position, said holding means being energized in response to the movement of said engine engaging member to engine engaging position.

2. In an engine starter, in combination with an engine engaging member, means for rotating said engine engaging member, said rotating means including a flywheel and a releasable clutch connecting said flywheel to said engine engaging member, means for moving said engine engaging member to engine engaging position, and means for electrically holding said clutch in released position, said holding means being energized in response to the movement of said engine engaging member to engine engaging position.

8. In an engine starter, in combination with an engine engaging member, means for rotating said engine engaging member, said rotating means including a motor and gear train, additional rotating means including a flywheel and a releasable clutch connecting said flywheel to said gear train, means for moving said engine ing member remains in engine engagingposition. I

4. In an engine starter, in combination with an engine engaging member, means for rotating sa1d engine engaging member, said rotating means including a motor and gear train, additional rotating means including a flywheel and a releasable clutch connecting said flywheel to said gear train, means including a longitudinally movable rod for moving said engine engaging member to engine engaging position, and means for electrically holding said clutch in released position, said holding means being energized in response to the movement of said engine engaging member to engine engaging position.

5. In an engine starter, in combination with an engine engaging member, means for rotating said engine engaging member, said rotating means including a motor and gear train, additional rotating means including a flywheel and a releasable clutch connecting said flywheel to said gear train, means including a longitudinally movable rod for moving said engine engaging member to engine engaging position, means for electrically holding said clutch in released position, said holding means being energized in response to the movement of said engine engaging memher to engine engaging position, and means responsive to partial rotation of said rod to reengage said clutch.

6. In an engine starter, in combination with an engine engaging member, means for rotating said engine engaging member, said rotating means including a motor and gear train, an inertia member also rotatable by said motor, means including a normally engaged clutch for drivably connecting said inertia member and gear train, electromagnetic means for disengaging said clutch, manual means for moving said engine engaging member to engine engaging position, a source of current, and means shiftable with said manual means for connecting said electromagnetic means with said source of current, to energize said electromagnetic means and thereby cause disengagement of said clutch concurrently with movement of said engine engaging member to engine engaging position.

ROMEO M. NARDONE. 

